An aircraft, and in particular a helicopter type rotorcraft, usually includes gravity filler means in order to fill a tank using rudimentary means, e.g. a simple pipe.
By way of example, gravity filler means comply with the standard known under the name Stanag 3212. Conventionally, gravity filler means comprise an inlet duct opening out to a screen so as to avoid filling the tank with all kinds of pollutant.
The drawback of such gravity filling lies in particular in the time taken for filling, which remains relatively long.
In parallel, the fuel system is optionally provided with means enabling it to be filled under pressure, e.g. provided with a catch complying with the standard known under the name ISO 45. Document FR 2 226 603 presents a pressure filler valve provided with a solenoid enabling it to open.
Means for delivering fluid under pressure, e.g. a tanker truck, are then connected to the pressure filler means via a catch wheel so as to enable the tank to be filled very quickly.
The pressure filling valve may include mechanical end-of-filling control means that do not require the aircraft to be electrically powered, or electrical end-of-filling control means that require the aircraft to be electrically powered.
In addition, as described in document U.S. Pat. No. 4,328,844, a pressure filler value may also enable defueling to be performed quickly.
Thus, depending on the equipment required, an aircraft may include solely means for filling by gravity, means for filling by gravity and a pressure filler valve provided with mechanical end-of-filling control means, or indeed with gravity filler means and a pressure filler valve provided with electrical end-of-filling control means.
In order to cover these three different options, it is appropriate to provide three different versions of the aircraft, thereby leading in practice to significant cost and difficulties.
Document U.S. Pat. No. 5,289,900 describes means for filling a lubricant tank provided with a first filler orifice for filling by gravity and a second filler orifice for filling under pressure. In addition, the filler means include a discharge orifice enabling excess fluid to be removed.
Under such circumstances, the filler means according to that document U.S. Pat. No. 5,289,900 allow a leakage flow in the event of overflow, but do not provide means for stopping filling in mechanical or electrical manner.